Indicator dial



June 26, 1945. F. B. BRAND INDICATOR DIAL Filed Feb. .9, 1944 lNvENToR Frederick" B. ,Brun d BY wav Fatenteei .Hime 6, i945 NITED ,s'rA'rEs PATENT ori-fica l INDICATOR DIAL Frederick B. Brand, Hollis, N. Y., assigner tol Control Instrument Company, Inc., Brooklyn, N. Y.,4 i a corporation-of New York Application February 9, 1944, SeriaiNo.v 521,705

e claims. (ci. iis-12e) Thisinvention relates to improvements in indicaters and has particular reference lto a dial construction such as may be employed on navigational, iire control, and other like instruments.

As is well-known, dials for use on instruments of the above character are illuminated and; -here- ,tofore, it'has been customary to make such dials out its area while the inner plate 9, made of a.

which readily lends itself to engraving operations, e

but the diiliculty experienced with this material,

especially when used to is ,that of warpage.

According to (the present invention, the above difficulty is overcome by the provision of a dial of improved construction .the elements of'which may be easily assembled and adapted for mountmake larger size dials,

ing upon a hub when the dial is to be coupled toa shaft, and wherein stiffening plates forming a part of the dialhave their peripheral portions secured to the index ring oisaid dial and their central portions engaging each other in such manner that the possibility of warping is practically eliminated and the stiifening components of the dial will impart a minimum moment of inertia. Theinventive idea involved is capable of re-` ceiving a variety of mechanical expressions, one of which for purposes of illustration is -shown in the accompanying drawing; but it is to be exlpressly understood that said drawing is Vused only to describe :the invention as a whole and not to define the limits thereof, reference being had to the appended claims for this purpose.

In the drawing-- lel to the central portion of said plate, is slightly Fig. 1 is a front elevation of a dial constructed Fig. 5 is an enlarged sectional view of aI portion of the hub assembly.

The preferred form of the invention is shown mounted upon a hub 5, as when the dial is to be coupled to the shaft of an instrument, and said hub is provided with an annular flange 6 slightly offset from .the outer end of the hub toY provide an annular shoulder l'. y

The dial comprises outer and inner s 'ifening plates t and 9, respectively, which are adapted to be mounted upon the ange 6 of said hub and abutted against the shoulder l Ithereof so as to retain said plates in concentric relation to :the axis of' the dial. The inner or central portion ofithe plates 8 and 9r contact each other andl said plates are held inplace by a central clamping disc I0 which 'overlies the inner portion of said plate 8 and which is secured to the hub 5 by screws II. The outer plate 8 is hat throughsuitable resilient material, is inwardly olset at I2 to provide an intermediate portion Il? thereof which inclines outwardly toward the plate when-V the parts are in assembled position. Before the plate 9 is assembled with other elementsof the dial, as shown in Fig. 4, the peripheral portmn M thereof, which is slightly'bent so as to be at an angle to the portion I3 `and in a plane paralolset inwardly with respect tothelatter portion so that when the stiffening plates are brought together and assembled, as in Fig. 3, said plate 9 will be exed from its normal `condition and thus placed under tension to cause its central or hub"portion to exert outward pressureagainst the adjacent central portion of the plate 8, .thereby increasing the stiffeningefrect of the combined plates. A series of openings I5 may be provided inthe portion I3 of the plate 9 so 'as to materially lighten said plate and economize in the amount of material used. 4

To complete the dial, there is provided an index ring I6 of narrow width relative to th-eover-all diameter of the dial, and. which maybe made of a plastic having translucent characteristics so that when thev outer surface is coated with a masking paint in accordance with standard practice and the index markings Il are engraved about its periphery, these markings will be clearly visible whenA the dial is illuminated from the back or underneath side thereof.- Said ring I8 has its inner portion disposed between the plates' 8 and 9 and is secured to said plates by ,any suitable means such as a series of rivets I8 which also accomplish the purpose of xingrthe outer portions of the two plates relative to each other.

From the foregoing it will be obvious that the elements of the dial may be easily and quickly espande assembled and that when so assembled the plates tions and the plane ot the latter portion oi said 8 and 9 will combine to rigidly maintain the index plate, before assembly oi.' the plates, being latring in position and prevent any warping of the orally oilset from the plane of said central pordial and impart thereto a minimum moment oi tion, and means to secure together said ring and inertia. n the peripheral portions of said plates.

What is claimed is: il. In an instrument dial, ahub havingailange, l. In an instrument dial adapted for mounting a pair oi stiilening plates having central abutupona hub when coupling said dial to ashait, tint portions one oi which rests nrnini said said dini comprising an index ring capable op hanne, a central clamping disc secured to saidv loing oonoentriooly anonnr door nid hun l0 int in nnnyinr capannoni with the nbntiirr ySiiifening plaies having peripheral pgriions en. ilOl'iOll 0f the Other 0f Stid plates, the l'stildmtd A gaging sai' ring andtheir centra-1 portion; freely Portions 0f Sa plates to said ring an paging said ring and their central portions en- Platt having all intermediate poriimiofftet from gagingeanhoiher, Oneof said plaeesbeing spring its central portion and extending outwardly in biased so as to exert pressure against the other a peripheral direction therefrom and inclined plate, and means to secure the peripheral por- 15 towards said other plate and further having an tions of Sad plates e0 said Img, outer portion which, before assembly of said 2. In an instrument dial adapted for mounting Plates, 1S in a plane parallel t0 butv Offset from upon a hub when coupling the dial to a', shaft, said central portion so that the latter will exert said dial comprising an index ring capable of K outward pressure Vagainst', the central portion oi.' i

being concentrically arranged about said hub, 2o Said other plate,anndexri11g positioned betwen stiienng. ateshaving peripheral portions en- Said Plates, an means t0 Secure thevpel'ipherl cl to each amigas-rug eazlzxh other. one of said plate being re other its in IH relative to said. central and peripheral pox-- z5 F'REBDEZRICK B. BRAND. 

